/*####COPYRIGHTBEGIN####
 -------------------------------------------
 Copyright (C) 2009 Steve Karg

 This program is free software; you can redistribute it and/or
 modify it under the terms of the GNU General Public License
 as published by the Free Software Foundation; either version 2
 of the License, or (at your option) any later version.

 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.

 You should have received a copy of the GNU General Public License
 along with this program; if not, write to:
 The Free Software Foundation, Inc.
 59 Temple Place - Suite 330
 Boston, MA  02111-1307, USA.

 As a special exception, if other files instantiate templates or
 use macros or inline functions from this file, or you compile
 this file and link it with other works to produce a work based
 on this file, this file does not by itself cause the resulting
 work to be covered by the GNU General Public License. However
 the source code for this file must still be made available in
 accordance with section (3) of the GNU General Public License.

 This exception does not invalidate any other reasons why a work
 based on this file might be covered by the GNU General Public
 License.
 -------------------------------------------
####COPYRIGHTEND####*/
#include <stdint.h>
/* BACnet Stack defines - first */
#include "bacnet/bacdef.h"
/* BACnet Stack API */
#include "bacnet/bacdcode.h"
#include "bacnet/getevent.h"

/** @file getevent.c  Encode/Decode GetEvent services */

/**
 * @brief Encode APDU for GetEvent-Request service
 * @param apdu Pointer to a buffer, or NULL for length
 * @param lastReceivedObjectIdentifier  Object identifier
 * @return Bytes encoded.
 */
int getevent_apdu_encode(uint8_t *apdu,
    BACNET_OBJECT_ID *lastReceivedObjectIdentifier)
{
    int len = 0;
    int apdu_len = 0;

    /* encode optional parameter */
    if (lastReceivedObjectIdentifier) {
        len = encode_context_object_id(apdu, 0,
            lastReceivedObjectIdentifier->type,
            lastReceivedObjectIdentifier->instance);
        apdu_len += len;
    }

    return apdu_len;
}

/**
 * @brief Encode the GetEvent-Request service
 * @param apdu  Pointer to the buffer for encoding into
 * @param apdu_size number of bytes available in the buffer
 * @param data  Pointer to the service data used for encoding values
 * @return number of bytes encoded, or zero if unable to encode or too large
 */
size_t getevent_service_request_encode(
    uint8_t *apdu, size_t apdu_size, 
    BACNET_OBJECT_ID *data)
{
    size_t apdu_len = 0; /* total length of the apdu, return value */

    apdu_len = getevent_apdu_encode(NULL, data);
    if (apdu_len > apdu_size) {
        apdu_len = 0;
    } else {
        apdu_len = getevent_apdu_encode(apdu, data);
    }

    return apdu_len;
}

/** Encode service
 *
 * @param apdu APDU buffer to encode to.
 * @param invoke_id Invoke ID
 * @param lastReceivedObjectIdentifier  Object identifier
 *
 * @return Bytes encoded.
 */
int getevent_encode_apdu(uint8_t *apdu,
    uint8_t invoke_id,
    BACNET_OBJECT_ID *data)
{
    int len = 0; /* length of each encoding */
    int apdu_len = 0; /* total length of the apdu, return value */

    if (apdu) {
        apdu[0] = PDU_TYPE_CONFIRMED_SERVICE_REQUEST;
        apdu[1] = encode_max_segs_max_apdu(0, MAX_APDU);
        apdu[2] = invoke_id;
        apdu[3] = SERVICE_CONFIRMED_GET_EVENT_INFORMATION;
    }
    len = 4;
    apdu_len += len;
    if (apdu) {
        apdu += len;
    }
    len = getevent_apdu_encode(apdu, data);
    apdu_len += len;

    return apdu_len;
}

/** Decode the service request only
 *
 * @param apdu APDU buffer to encode to.
 * @param apdu_len Valid bytes in the buffer.
 * @param lastReceivedObjectIdentifier  Object identifier
 *
 * @return Bytes encoded.
 */
int getevent_decode_service_request(uint8_t *apdu,
    unsigned apdu_len,
    BACNET_OBJECT_ID *lastReceivedObjectIdentifier)
{
    unsigned len = 0;

    /* check for value pointers */
    if (apdu_len && lastReceivedObjectIdentifier) {
        /* Tag 0: Object ID - optional */
        if (!decode_is_context_tag(&apdu[len++], 0)) {
            return -1;
        }
        if (len < apdu_len) {
            len += decode_object_id(&apdu[len],
                &lastReceivedObjectIdentifier->type,
                &lastReceivedObjectIdentifier->instance);
        }
    }

    return (int)len;
}

int getevent_ack_encode_apdu_init(
    uint8_t *apdu, size_t max_apdu, uint8_t invoke_id)
{
    int apdu_len = 0; /* total length of the apdu, return value */

    if (apdu && (max_apdu >= 4)) {
        apdu[0] = PDU_TYPE_COMPLEX_ACK; /* complex ACK service */
        apdu[1] = invoke_id; /* original invoke id from request */
        apdu[2] = SERVICE_CONFIRMED_GET_EVENT_INFORMATION;
        apdu_len = 3;
        /* service ack follows */
        /* Tag 0: listOfEventSummaries */
        apdu_len += encode_opening_tag(&apdu[apdu_len], 0);
    }

    return apdu_len;
}

int getevent_ack_encode_apdu_data(uint8_t *apdu,
    size_t max_apdu,
    BACNET_GET_EVENT_INFORMATION_DATA *get_event_data)
{
    int apdu_len = 0; /* total length of the apdu, return value */
    BACNET_GET_EVENT_INFORMATION_DATA *event_data;
    unsigned i = 0; /* counter */

    (void)max_apdu;
    if (apdu) {
        event_data = get_event_data;
        while (event_data) {
            /* Tag 0: objectIdentifier */
            apdu_len += encode_context_object_id(&apdu[apdu_len], 0,
                event_data->objectIdentifier.type,
                event_data->objectIdentifier.instance);
            /* Tag 1: eventState */
            apdu_len += encode_context_enumerated(
                &apdu[apdu_len], 1, event_data->eventState);
            /* Tag 2: acknowledgedTransitions */
            apdu_len += encode_context_bitstring(
                &apdu[apdu_len], 2, &event_data->acknowledgedTransitions);
            /* Tag 3: eventTimeStamps */
            apdu_len += encode_opening_tag(&apdu[apdu_len], 3);
            for (i = 0; i < 3; i++) {
                apdu_len += bacapp_encode_timestamp(
                    &apdu[apdu_len], &event_data->eventTimeStamps[i]);
            }
            apdu_len += encode_closing_tag(&apdu[apdu_len], 3);
            /* Tag 4: notifyType */
            apdu_len += encode_context_enumerated(
                &apdu[apdu_len], 4, event_data->notifyType);
            /* Tag 5: eventEnable */
            apdu_len += encode_context_bitstring(
                &apdu[apdu_len], 5, &event_data->eventEnable);
            /* Tag 6: eventPriorities */
            apdu_len += encode_opening_tag(&apdu[apdu_len], 6);
            for (i = 0; i < 3; i++) {
                apdu_len += encode_application_unsigned(
                    &apdu[apdu_len], event_data->eventPriorities[i]);
            }
            apdu_len += encode_closing_tag(&apdu[apdu_len], 6);
            event_data = event_data->next;
        }
    }

    return apdu_len;
}

int getevent_ack_encode_apdu_end(
    uint8_t *apdu, size_t max_apdu, bool moreEvents)
{
    int apdu_len = 0; /* total length of the apdu, return value */

    (void)max_apdu;
    if (apdu) {
        apdu_len += encode_closing_tag(&apdu[apdu_len], 0);
        apdu_len += encode_context_boolean(&apdu[apdu_len], 1, moreEvents);
    }

    return apdu_len;
}

int getevent_ack_decode_service_request(uint8_t *apdu,
    int apdu_len, /* total length of the apdu */
    BACNET_GET_EVENT_INFORMATION_DATA *get_event_data,
    bool *moreEvents)
{
    uint8_t tag_number = 0;
    uint32_t len_value = 0;
    int len = 0; /* total length of decodes */
    uint32_t enum_value = 0; /* for decoding */
    BACNET_UNSIGNED_INTEGER unsigned_value = 0;
    BACNET_GET_EVENT_INFORMATION_DATA *event_data;
    unsigned i = 0; /* counter */

    /* FIXME: check apdu_len against the len during decode   */
    event_data = get_event_data;
    if (apdu && apdu_len && event_data && moreEvents) {
        if (!decode_is_opening_tag_number(&apdu[len], 0)) {
            return -1;
        }
        len++;
        while (event_data) {
            /* Tag 0: objectIdentifier */
            if (decode_is_context_tag(&apdu[len], 0)) {
                len += decode_tag_number_and_value(
                    &apdu[len], &tag_number, &len_value);
                len += decode_object_id(&apdu[len],
                    &event_data->objectIdentifier.type,
                    &event_data->objectIdentifier.instance);
            } else {
                return -1;
            }
            /* Tag 1: eventState */
            if (decode_is_context_tag(&apdu[len], 1)) {
                len += decode_tag_number_and_value(
                    &apdu[len], &tag_number, &len_value);
                len += decode_enumerated(&apdu[len], len_value, &enum_value);
                if (enum_value < EVENT_STATE_MAX) {
                    event_data->eventState = (BACNET_EVENT_STATE)enum_value;
                } else {
                    return -1;
                }
            } else {
                return -1;
            }
            /* Tag 2: acknowledgedTransitions */
            if (decode_is_context_tag(&apdu[len], 2)) {
                len += decode_tag_number_and_value(
                    &apdu[len], &tag_number, &len_value);
                len += decode_bitstring(&apdu[len], len_value,
                    &event_data->acknowledgedTransitions);
            } else {
                return -1;
            }
            /* Tag 3: eventTimeStamps */
            if (decode_is_opening_tag_number(&apdu[len], 3)) {
                len += decode_tag_number_and_value(
                    &apdu[len], &tag_number, &len_value);
                for (i = 0; i < 3; i++) {
                    len += bacapp_decode_timestamp(
                        &apdu[len], &event_data->eventTimeStamps[i]);
                }
            } else {
                return -1;
            }
            if (decode_is_closing_tag_number(&apdu[len], 3)) {
                len += decode_tag_number_and_value(
                    &apdu[len], &tag_number, &len_value);
            } else {
                return -1;
            }
            /* Tag 4: notifyType */
            if (decode_is_context_tag(&apdu[len], 4)) {
                len += decode_tag_number_and_value(
                    &apdu[len], &tag_number, &len_value);
                len += decode_enumerated(&apdu[len], len_value, &enum_value);
                if (enum_value < NOTIFY_MAX) {
                    event_data->notifyType = (BACNET_NOTIFY_TYPE)enum_value;
                } else {
                    return -1;
                }
            } else {
                return -1;
            }
            /* Tag 5: eventEnable */
            if (decode_is_context_tag(&apdu[len], 5)) {
                len += decode_tag_number_and_value(
                    &apdu[len], &tag_number, &len_value);
                len += decode_bitstring(
                    &apdu[len], len_value, &event_data->eventEnable);
            } else {
                return -1;
            }
            /* Tag 6: eventPriorities */
            if (decode_is_opening_tag_number(&apdu[len], 6)) {
                len += decode_tag_number_and_value(
                    &apdu[len], &tag_number, &len_value);
                for (i = 0; i < 3; i++) {
                    len += decode_tag_number_and_value(
                        &apdu[len], &tag_number, &len_value);
                    len +=
                        decode_unsigned(&apdu[len], len_value, &unsigned_value);
                    event_data->eventPriorities[i] = (uint32_t)unsigned_value;
                }
            } else {
                return -1;
            }
            if (decode_is_closing_tag_number(&apdu[len], 6)) {
                len += decode_tag_number_and_value(
                    &apdu[len], &tag_number, &len_value);
            } else {
                return -1;
            }
            if (decode_is_closing_tag_number(&apdu[len], 0)) {
                len += decode_tag_number_and_value(
                    &apdu[len], &tag_number, &len_value);
                event_data->next = NULL;
            }
            event_data = event_data->next;
        }
        if (decode_is_context_tag(&apdu[len], 1)) {
            len += decode_tag_number_and_value(
                &apdu[len], &tag_number, &len_value);
            if (len_value == 1) {
                *moreEvents = decode_context_boolean(&apdu[len++]);
            } else {
                *moreEvents = false;
            }
        } else {
            return -1;
        }
    }

    return len;
}
